Underwater wellhead with remotelydetachable flow line



P 1962 R. GEER ETAL 3,052,299

UNDERWATER WELLHEAD WITH REMOTELY-DETACHABLE FLOW LINE Filed Aug. 25,1959 3 Sheets-Sheet 1 INVENTORSIV R.L.GEER

| s. OTTEMAN umwuzz THEIR AGENT 3 Sheets-Sheet 2 Sept. 4, 1962 R. L.GEER ETAL UNDERWATER WELLHEAD WITH REMOTELY-DETACHABLE FLOW LINE FiledAug. 25, 1959 THEIR AGENT A m m m S T R "a T H ma; m m 6 W B K .\o=\ omN: *2 \\v 2. N; t. w N \Vw E \d 7 7/4 zyflifi fl d w A \N 2: 1 91 :6 "32. :3 87 mo. my $29 9. 5 mm \5 f m w: v 2 A mm ,mmmm E v E g m: E NE mmSept. 4, 1962 R. 1 GEER ETAL UNDERWATER WELLHEAD WITHREMOTELY-DETACHABLE FLOW LINE 3 Sheets-Sheet 3 Filed Aug. 25, 1959 ON N:

lNVENTORS R. L. GEER L. G. OTTEMAN BYzd THEIR AGENT United States PatentO 3,052,299 UNDERWATER WELLIEAD WITH REMUTELY- DETACHABLE FLGW LlNERonald L. Geer and Lloyd G. Gtteman, Houston, Tex.,

assignors to Shell Gil Company, a corporation of Delaware Filed Aug. 25,1959, Ser. No. 835,930 8 Claims. (Cl. 166-665) The present apparatusrelates to oil well equipment for use at underwater locations andpertains more particularly to an underwater wellhead apparatus with aremotely-detachable flow line which includes a power-actuated andremotely-operable pipeline connector for connecting the wellheadassembly to a underwater pipeline, such as one running along the oceanfloor.

The wellhead apparatus of the present invention is adapted to be used toclose wellhead assemblies of the type described in copending patentapplication, Serial No. 834,096, filed August 17, 1 959. A recentdevelopment in the field of oil well drilling is the completion of wellsat offshore locations with a wellhead assembly positioned on or close tothe ocean floor out of the way of ships which might otherwise damage itin the event of a collision. Equipment positioned on the ocean floor,however, is exposed to conditions such as the corrosive nature of thesea water and the presence of marine life which tends to grow and becomeencrusted on metallic structures below the surface of the water.

Since it is necessary from time to time to go back into a well whereverit has been completed for servicing or work-over operations, it isdesirable to have an underwater wellhead structure of suitable design sothat it could be readily removed from the underwater wellhead and raisedto the surface. An underwater wellhead structure of this type is shownand described in copending patent application, Serial No. 834,096, filedAugust 17, 1959.

On removing a wellhead assembly from the top of the Well in accordancewith present practice, a diver must first be sent to the ocean floor todisconnect the production flow line from the wellhead assembly.Otherwise, the production flow line adjacent the wellhead assembly mustbe raised to the surface of the water along with the wellhead assemblywhen the latter is removed from an underwater wellhead and raised to thesurface. Divers can be used effectively only at relatively shallow waterdepths of up to about 150 feet.

It is therefore an object of the present invention to provide anunderwater wellhead apparatus which can be readi- 1y detached from anunderwater wellhead flow line by operators working at a remote location,such as on a barge or other vessel positioned on the surface of thewater above the well site.

It is also an object of the present invention to provide an underwaterwellhead assembly with a remotely detachable flow line extendingtherefrom in a manner such that after disconnecting the flow line fromthe wellhead assembly, either the wellhead assembly or the disconnectedflow line may be raised independently to the surface of the waterwithout interfering with the other equipment at the wellhead and withoutthe necessity of moving both the flow line and the wellhead assembly.

A further object of the present invention is to provide apparatus forlowering one end of an underwater production flow line down to anunderwater wellhead in a manner such that the lowered end of the flowline is in coaxial register with the cooperating end of the productionflow line at a point after it leaves the wellhead assembly.

These and other objects of the present invention will be understood fromthe following description taken with regard to the drawing, wherein:

FIGURE 1 is a schematic view illustrating a wellhead 3,052,299 PatentedSept. 4, 1962 assembly of the present invention positioned on the oceanfloor;

FIGURE 2 is a side view of the pipeline coupling lowering mechanismshown in FIGURE 1; and,

FIGURES 3 and 4 are views taken in longitudinal crosssection of ahydraulically-operated pipeline connector or coupling, of the type to beused with the wellhead assem bly of FIGURE 1, in its uncoupled andcoupled positions, respectively.

Referring to FIGURE 1 of the drawing, a wellhead support structure 11 isshown as comprising a series of interconnected girders 12 andcross-bracing member 13. The bottom-most girders 12 may rest on a cementpad 14 which may be poured on the ocean floor in a manner described incopending patent application, Serial No. 830,- 538, filed July 30, 1959.A casinghead 15 is fixedly secured to the wellhead support structure 11and is preferably installed therewith at the time the wellhead supportstructure is positioned over the well to be drilled.

Suitable apparatus is provided for guiding well equipment into placeupon the casinghead 15, both during and after drilling operations. Inthe particular apparatus illustrated in FIGURE 1, the vertical members17 of the wellhead support structure comprise vertical guide tubes 17each having a vertical slot 18 cut through the wall thereof. Each pieceof equipment to be lowered into place on the well casinghead 15 may beprovided with two or more guide arms 21 adapted to extend through theguide slot 18 of two or more guide tubes 17 where they are connected toguide cones 22. The guide cones are of a diameter slightly less than theinner diameter of the guide tubes 17 and preferably have a lower portionthat tapers downwardly.

Preferably, each of the guide tubes 17 has a cone-shaped flange 23attached to its upper end which serves to align the guide cones 22 asthey move downwardly into the guide tubes 17. Each of the guide cones 22is provided with a vertical hole therethrough of a diameter slightlylarger than the guiding cables 24 which are secured at their ends to thewellhead support structure within the bottom of the guide tubes 17 andextend upwardly to the surface where they are suspended from a drillingvessel or barge (not shown) from which operations are being carried out.

In FIGURE 1 the guide arms 21 are shown as being connected to acontainer 25 which may be employed to surround the wellhead assembly orproduction control unit of the well. For purposes of simplifying thedrawing and description thereof, the wellhead assembly of the presentinvention is shown as comprising a pair of control valves 26 and 27which are positioned in the production flow line 28 coming from thewell. Although the well is illustrated as having a single string of wellcasing 30 and a single string of production tubing 31 extendingdownwardly into the well, it is to be understood that the presentwellhead apparatus could be employed with wells having multiple stringsof casing and tubing.

Normally, the production control unit or wellhead assembly enclosedwithin the container 25 comprises the necessary piping, valves, chokes,and other equipment normally connected together and mounted on the topof a well, and known as a Christmas tree, together with the necessaryhydraulic or electrical systems including pumps, reservoirs, motors, andetc, to operate the valves at the head of the well from a remotelocation. A typical example of a suitable underwater production controlunit or well head assembly for use at an offshore well location, and themanner in which it is locked to the casinghead 15, is shown anddescribed in copendinig patent application, Serial No. 834,096, filedAugust 17, 1959.

The container 25 and the wellhead assembly contained therein is normallylowered into place by means of a string of pipe 32 known as a runningstring which has a running head 33 attached to the lower end thereofwhich may be connected to the top of container 25 or to its lubricator34. The lubricator or wellhead closure 34 may be of any desired typesuitable for use in offshore underwater wellhead assemblies. A typicallubricator or wellhead closure of this type is shown and described incopending application, Serial No. 830,587, filed July 30, 1959. Awellhead closure of this type permits re-entry into the well for wellcontrol or work-over purposes. During normal production of a well therunning string 32, running head 33 and any pressure tubing strings 35and 36 which may be contained therein, are disconnected from thewellhead assembly and drawn to the surface. When not in use the guidecables 24 are dropped to the ocean floor where they may later beretrieved by grappling hooks or other suitable means when it is desiredto use them again to lower equipment to the wellhead. During work-overor other operations on the well, the running string 32 and the runninghead 33 may be replaced by a marine conductor pipe string and a landinghead or seal (not shown).

The production flow line 28 as it leaves the top of the wellheadassembly or the container 25 is preferably, though not necessarily,curved in an arc of substantial radius so that various tools,instruments, or other devices may be circulated through the productionflow line and down into the well. As the flow line 28 passeshorizontally by the container 25 it is preferably rigidly fixed theretoas by welding, clamping, bolting, etc.

A pipeline coupling or a pipeline connector consisting of a femaleportion 40 and a male portion 41 is installed in the production flowline 28 at a point close to the wellhead assembly or its container 25.Preferably, the male portion 41 of the coupling is fixedly mounted on acarriage 42 which is, in turn, fixedly secured by means of suitablebraces 43, 44 and 45 (FIGURE 2) to one or more guide cones 46 and 47.The guide cones 46 and 47 are slidably mounted on a guide cable 48 whichpasses downwardly through a vertical guide tube 51 which is similar indesign to guide tubes 17 and is provided with a slot 52 therein and acone-shaped flange 53 on the top thereof. A suitable stop member isprovided in the guide tube 51 so as to limit the downward movement ofthe cones 46 and 47 Within the guide tube 51 so that the carriage 42, atthe end of its travel, is positioned with the male portion 41 of thecoupling on a level with the fem-ale portion 40. Instead of employing astop member within the guide tube 51, the slot 52 therein could beterminated at some point above the bottom of the tube 51 so as to limitthe downward travel of the lower guide cone 47.

The precise placement of the slot 52 in the guide tube 51 serves asaligning means between the carrier 42 and the cable 48 to position themale portion 41 of the coupling in substantially coaxial register andspaced relationship with the female portion 40 of the coupling. In someinstallations it may be found more advantageous to lower the maleportion 41 of the coupling on its carriage 42 that is suspended betweentwo parallel guide cables 48 which terminate in two parallel guide tubes51. The portion 28a of the production flow line extending from the maleportion 41 of the coupling is preferably flexible, but may also be apreformed rig-id section, to facilitate positioning it on the oceanfloor and attaching it to the female portion 40 of the coupling. In theevent that the well has two or more production flow lines, then thewellhead assembly would be provided with two or more couplings.

The pipeline coupling 40-41 to be used in connecting the underwaterpipeline 28a to the wellhead assembly may be of any suitable type whichis provided with a housing to protect its working parts againstcorrosion caused by the sea water and the growth of marine organisms.The connector 4041 is preferably positioned substantially horizontally,i.e., up to about 45 degrees from the horizontal, for ease in making theconnection. Additionally, the pipeline connector of the presentinvention is positioned to one side of the present wellhead assembly sothat after the pipeline coupling 4tl-41 is disconnected, either the maleend 41 of the coupling together with its pipeline 28a, or the female end49 together with the wellhead assembly and container 25, can be raisedto the surface independently while the other portion of the coupling andits attached equipment remain at the ocean floor or in their originalposition. The coupling 46-41 is of the power-actuated, remotely-operatedtype which may be of either the pneumatic, hydraulic, or electrical typewith power leads or fluid-pressure operating lines running independentlyto the surface. However, the coupling 49 41 is preferably of theremotely-controlled, hydraulically-operated pipeline coupling as shownin FIGURES 3 and 4 of the drawing. The female portion 49 of the couplingcontains both the sealing and locking mechanism for forming a fluidtightseal with the male portion 4 1 of the coupling. The female portion ofthe coupling comprises a central tubular member 61 which forms anextension of the production flow line 28 and is fixedly secured theretoas by threads 6-2. The outer surface of tubular member 61 is reduced indiameter as at 63 so as to seat the end of a sleeve 64 which extendsoutwardly from the flow line 28. The outer surface of the tubular member61 is further reduced in diameter, as at 65, to provide an annular flowpassage 66 which is in communication at one end with the pressure fluidconduit 56. The outer surface of the sleeve 64 and the outer surface ofthe tubular member 61 and its largest diameter are fitted flush so as toserve as a guide tube on which a tubular or sleevetype piston 67 isslidably mounted. The inner diameter of the piston 67 is enlarged over aportion of the length thereof in order to form an annular fluid passage70 between the inside of the piston 6-7 and the outside of the sleeve64.

The outside wall, forming the chamber in which piston 67 is slidablymounted, is formed by a coaxial sleeve or tubular member 71 which isfixedly secured to the end of the pipe 28 as by threads 79. The innerdiameter of the tubular member 71 is increased over a substantialportion of its length to form an annular fluid passageway 72 between theouter wall of the piston 67 and the inner wall of the tubular member 71.The annular fluid passageway or chamber 72 forms the piston chamber inwhich the head 73 of the piston 67 moves. The length of the chamber 72determines the length of the stroke of the piston 67. Thus, it isapparent that the length of the chamber 72 must be at least equal to thedistance the opposite end 68 of the piston 67 must travel in order to bepositioned in fluidtight engagement within a recessed portion 74 of themale portion 41 of the coupling.

Extending through the tubular member 71 which forms the cylinder wallfor pistonhead 7 3 is a fluid passageway 75 in communication between thepressure fluid line 55 at one end of the apparatus and the space outsidethe other end of the tubular member. Extending through a substantiallength of the piston wall 67 is a fluid passageway 76 which is incommunication through a port 77, just below the head 73 of the piston67, with the annular fluid chamber 72. The annular flow passage 66 is incommunication through conduit 73 with the pressure fluid line 56 at theend of the coupling.

A collar 81, forming a tandem piston head with piston head 73, isfixedly secured, as by threads 82, on the outside of the piston 67 justbelow the tubular member 71, or at a distance from the head 73 of thepiston 67 equal to or slightly greater than the stroke of the piston.Fixedly secured to the outside surface of the annular collar or tandempiston 81 is a cylindrical housing 84 which is also in slidingfluidtight engagement with the end 85 of the tubular member 71.Preferably, the end 85 of the tubular member 71 is enlarged in diameterfor design purposes so that a collar 81 of substantial thickness may beemployed in order to increase the effective area against which pressurefluid acts, as well as to accommodate the necessary valve and conduitarrangement for unlatching the present coupling.

The piston head 73 moves within a chamber formed by the annular sleeve64 and the tubular member 71. While it is possible to consider theenlarged end 85 of the tubular member 71 to be a piston moving withinthe chamber formed by the cylindrical housing 84 on the outside and thepiston 67 on the inside, for purposes of clarification the enlarged end85 of the tubular member 71 will be considered hereinbelow as thestationary end of a piston chamber since the tubular member is fixedlysecured at 72 to the flow line 28. Thus, the collar 81 will beconsidered to be a tandem piston fixedly secured to and movable withpiston 67, with the outside wall of piston 67 and the inside wall ofhousing 84 forming the piston chamber into which a pressure fluid isapplied to move the piston 67, collar 81 and housing 84 axially alongthe central tubular member 61. A port 83 in the tubular member 71 is incommunication between the fluid passage 75 therethrough and the spaceoutsidethereof at the end of chamber 72, whereby a pressure fluid may beapplied to the outer face of the piston 73 for driving it to the right.

The extending portion 36 of a cylindrical housing 84 is enlarged indiameter providing a wall of substantial thickness for containing thelocking mechanism of the present coupling. A portion of the wall of theend 36 of the cylindrical housing 84 is recessed to form a pistonchamber 90 in which an annular piston 91 is slidably mounted. The piston91 is fixedly secured to and slidable with a locking piston 92 which maybe either in ring form or may comprise a plurality of individual lockingelements adapted to engage a plurality of locking dogs 93 which areadapted to be seated in a locking groove 94 formed on the outer surfaceof the male portion of the coupling, as illustrated in FIGURE 4. Thelocking piston 92 is provided :with a downwardly sloping surface 95adapted to engage upwardly sloping surfaces 96 of the dogs 93 forraising the dogs 93 into the wall of the cylindrical housing 86 so thatthe female portion 41 of the coupling can be withdrawn.

The locking dogs or latching members 93 are springloaded in any suitablemanner, as by being provided with spring-like arms 97 which allow thedogs 93 to extend normally through slots 98. A locking head 101 iscarried at the end of the locking piston 92 for locking the dogs 93 inplace in the annular groove 94 of the male portion 41 of the coupling,as shown in FIG- URE 4.

In the locked position shown in FIGURE 4 of the drawing, a chamber 102is formed in back of piston 91 between the outer surface of the collar81 and the inner surface of the locking piston 92. At the same timeanother chamber 103 is formed between the collar 81 and the enlarged end85 of the tubular member 71 and between the cylindrical housing 84 andthe piston 67. In the locked position the chambers 102 and 103 are incommunication through fluid passageways 164 and 105 and throughpassageway 1118 of a spring-loaded valve 166 which has been forcedinwardly by the face 167 of the male portion 41 of the coupling to bepositioned, as shown in FIGURE 4, so that the passageways 104 and 105are in communication through 11113.

The piston 91 is provided with a flow passageway 110 while thecylindrical housing 84 is provided with passageway 111 and the collar 81is provided with passageway 112. These flow passageways 110, 111 and 112form a continuous flow passage so that in the unlatched position thechamber 90 formed on one side of the annular piston 91 is incommunication through flow passageways 110, 111, 112, 76 and 77 with theannular fluid chamber 72. The chamber 96 is also in communicationthrough a passageway 113 through the collar 81, through passageway 114in the piston 67 and through port 115 in the annular sleeve 64 so as tocommunicate through annular flow passage 66 and conduit 78 with thefluid pressure line 56. The annular fluid passageway 70 between thepiston 67 and the sleeve 64 is in communication at all times throughport 115 with the annular flow passageway 66 and thence through conduit78 with the pressure fluid conduit 56. The outer surface of the piston67 near the end 68 thereof is provided with suitable sealing means, suchfor example as O-ring seals or rings of packing, which act as a primaryseal between the male and female portions of the coupling. The innersurface of the cylindrical housing 84, or the outer surface of the malecoupling 41, is provided with a seal 120 which closes the space betweenthe housing 84 and the male portion 41 of the coupling in a fluidtightmanner. The ends of the female 40 and the male 41 portions of thecoupling are bevelled, as at 117 and 113, respectively, to aid inaligning the two portions of the coupling when the female portion isforced toward the male portion.

A connection is made between the male and female portions of thecoupling shown in FIGURE 3 by applying a pressure fluid from anysuitable source through conduit 55. The pressure fluid passes throughfluid passageway 75 and port 88 to exert pressure against pistons 81 and73, respectively, moving them to the right together with the cylindricalhousing 84 and the locking dogs 93. As the cylindrical housing 34approaches the male portion 41 of the coupling, tapered faces 117 and118 of the female and male portions of the coupling align the twoportions so that the end 68 of the piston 67, containing the sealingrings 116, moves into and is seated within the recessed opening '74 ofthe male portion 41 of the coupling. The end 63 of the piston 67continues to slide into the recessed portion 74 until the face 167 ofthe male portion 41 of the coupling forces the fluid transfer valve 106to the left, aligning the conduit 108 therein with conduits 104 and 165.At this time, the locking or latching dogs 93 are positioned over slots98 so they may enter the annular groove 94 in the outer surface of themale portion 41 of the coupling. With the valve 106 in the positionshown in FIGURE 4 of the drawing, the continued application of apressure fluid through conduits 55 and 75 and into chamber 103 causespressure to be exerted through conduits 1115, 168 and 104 and intochamber 1112 where pressure is applied to the right side of the piston91 causing locking piston 92 to move .to the left so that the lockinghead 1111 of the locking piston bears against the top of the locking dog93, thus anchoring it in place.

During the sealing and locking operations of the coupling describedabove, fluid in the annular chamber 72 is exhausted through port 77,passageways 76, 112, 111, 110 and into chamber 91} and thence throughpassage- Ways 113 and 114, port 115 and passageways 66, 78 and 56 to thehydraulic fluid reservoir (not shown).

To disengage the coupling shown in FIGURE 4, pressure fluid is appliedthrough conduits 56, 7.8 and 66 and. thence through port 115 andpassageways 71), 114 and 113 to exert a pressure on the left side ofpiston 91, thus forcing it to the right. As the locking piston 92 isforced to the right, the locking head 16 1 is removed from the top ofthe locking dog 93 and the downwardly sloping face of the locking piston92 engages the upwardly sloping face 96 of the locking dog 93 to raisethe spring-loaded locking dog 93 into its retracted position, as shownin FIGURE 3 of the drawing. As the piston 91 reaches the end of itstravel to the right, the conduit therein is brought into communicationwith the conduit 111 of the cylindrical housing so that pressure fluidfrom the chamber 90 flows through passageways 110, 111, 112, 76 and port77 to exert a pressure on the underside of the piston head 73, thuscausing it to move to the left. As the piston 91 moved to the right inFIGURE 4 to unlock the dogs 93, fluid in the chamber 102 is exhaustedthrough fluid passageways 194, 163 and 105 into the chamber res andthence through passageway 75 and conduit 55 to the hydraulic fluidreservoir (not shown). At the same time, fluid in the chamber 72 to theleft of the piston 73 is exhausted through port $8 and conduit 55 to thereservoir. in operation, pressure fluid may be supplied to unlock thecoupling of the present invention in a manner described in copendingpatent application, Serial No. 830,587, filed July 30 1959, wherein apair of tubing strings 35 and 56 (FIGURE 1) are inserted through arunning string or marine conductor 32 to supply pressure fluidselectively to conduits 55 and 56 leading to the coupling.

We claim as our invention:

1. An oflshore wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasing extending into a well drilled in the earth underlying said water,a wellhead assembly closing the top of said casing and secured thereto,said wellhead assembly having flow passage means therethrough, aproduction flow line connected to said wellhead assembly for conveyingproduction fluid therefrom, coupling means connected in said productionflow line near said well head assembly, a first portion of said flowline being secured to said wellhead assembly and having a first portionof said coupling means secured to the end thereof means adapted toextend between said wellhead apparatus and the surface of said water forlowering and positioning a cooperating second portion of said couplingmeans and another portion of flow line attached thereto in coaxialregister and spaced relationship with said first portion of saidcoupling means, and remotely-controlled power-actuated prime mover meanscarried by one portion of said coupling means for moving at least oneelement of said one portion axially into fluidtight connection with theother portion of said coupling means.

'2. An offshore wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasing and one string of well production tubing extending into a welldrilled in the earth underlying said water, a well head assembly closingthe top of said casing and removably secured thereto, said wellheadassembly having flow passage means therethrough, a production flow lineconnected to said wellhead assembly for conveying production fluidtherefrom, two-piece coupling means connected in said production flowline near said wellhead assembly, a first portion of said flow linebeing secured to said wellhead assembly and having a first portion ofsaid coupling means secured to the end thereof to one side thereof andlowerable therewith into place on the top of said well casing, guidecable means extending from said wellhead apparatus upwardly to thesurface of said water, carrier means slidably mounted on said guidecable means for lowering a cooperating second portion of said couplingmeans and another portion of flow line attached thereto to said wellheadassembly, aligning means cooperating with said carrier means and saidguide cable means for positioning said second portion of said couplingmeans in coaxial register and spaced relationship with said firstportion of said coupling means, and remotely-controlled power-actuatedprime mover means carried by one portion of said coupling means formoving at least one element of said one portion of coupling axially intofiuidtight connection with the other portion of said coupling means.

'3. An offshore wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasing and one string of well production tubing extending into a welldrilled in the earth underlying said Water, a wellhead assembly closingthe top of said casing and removably secured thereto, said wellheadassembly having flow passage means therethrough, a production flow lineconnected to said wellhead assembly for conveying production fluidtherefrom, two-piece coupling means connected in said production flowline near said wellhead assembly, a first portion of said flow linebeing secured to said wellhead assembly and having a first portion ofsaid coupling means secured to the end thereof to one side thereof andlowerable therewith into place on the top of said well casing, guidecable means extending from said wellhead apparatus upwardly t0 thesurface of said water, carrier means slidably mounted on said guidecable means for lowering a cooperating second portion of said couplingmeans and another portion of flow line attached thereto to said wellheadassembly, aligning means cooperating with said calrier means and saidguide cable means for positioning said second portion of said couplingmeans in coaxial register and spaced relationship with said firstportion of said coupling means, remotely-controlled power-actuatedpiston means for moving at least one element of said first portion ofcoupling axially into fluidtight connection with the other portion ofsaid coupling means, remotelycontrolled power-actuated locking means forlocking together the two portions of said coupling means, said pistonmeans and said locking means being both carried by one portion of saidcoupling means.

4. An offshore wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasing and one string of well production tubing and extending into awell drilled in the earth underlying said water, a wellhead assemblyclosing the top of said casing and removably secured thereto, saidwellhead assembly having flow passage means therethrough, said wellheadassembly including valve means for controlling the flow of fluid fromsaid production tubing, a rigid production flow line connected to saidwellhead assembly for conveying production fluid therefrom, two-piececoupling means connected in said production flow line near said wellheadassembly, a first portion of said flow line being secured to saidwellhead assembly and having a first portion of said coupling meanssecured to the end thereof to one side thereof and lowerable therewithinto place on the top of said well casing, guide cable rneans extendingfrom said wellhead apparatus upwardly to the surface of said water,carrier means slidably mounted on said guide cable means for lowering acooperating second portion of said coupling means and a portion of flowline attached thereto to said wellhead assembly, aligning meanscooperating with said carrier means and said guide cable means forpositioning said second portion of said coupling means in substantiallycoaxial register and spaced relationship with said first portion of saidcoupling means, remotely-controlled power-actuated piston means formoving at least one element of said first portion of coupling axiallyinto fluidtight connection with the other portion of said couplingmeans, remotely-controlled power-actuated locking means for lockingtogether the two portions of said coupling means, said piston means andsaid locking means being both carried by said first portion of saidcoupling means.

5. An oflshore wellhead apparatus to be positioned beneath the surfaceof water, said apparatus including at least one string of well casingand one string of well production tubing extending into a well drilledin the earth underlying said water, a wellhead assembly closing the topof said casing and removably secured thereto, said wellhead assemblyhaving flow passage means therethrougl 1, said wellhead assemblyincluding valve means for controlling the flow of fluid from saidproduction tubing, a rigid production flow line connected to saidwellhead assembly for conveying production fluid therefrom, two-piececoupling means connected in said production flow line near said wellheadassembly, a first portion of said flow line being secured to saidwellhead assembly and having a first portion of said coupling meanssecured to the end thereof to one side thereof and lowerable therewithinto place on the top of said well casing, a

plurality of guide cables extending from said wellhead apparatusupwardly to the surface of said water, carrier means slidably mounted onsaid guide cables for lowering a cooperating second portion of saidcOupling means and a flexible portion of flow line attached thereto tosaid wellhead assembly, aligning means formed by at least one slottedvertical guide tube secured to said Wellhead apparatus and having one ofsaid guide cables axially anchored therein, the diameter of said cablebeing greater than the Width of the slot in said guide tube, said slotadapted to receive said carrier means for positioning said secondportion of said coupling means in coaxial register and spacedrelationship with said first portion of said coupling means,remotely-controlled power-actuated piston means for moving at least oneelement of said first portion of coupling axially into fiuidtightconnection with the other portion of said coup-ling means,remotelycontrolled power-actuated locking means for locking t gether thetwo portions of said coupling means, said piston means and said lockingmeans being both carried by said first portion of said coupling means.

6. An offshore Wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasin extending into a Well drilled in the earth underlying said water,a wellhead assembly closing the top of said casing and secured thereto,said wellhead assembly having flow passage means therethrough incommunication with a string of well casing therein, a production flowline connected to said Wellhead assembly for conveying production fluidtherefrom, coupling means connected in said production flow line nearsaid wellhead assembly, a first portion of said flow line and a firstportion of said coupling means being fixedly positioned relative to saidwellhead assembly, a cooperating second portion of said coupling meansand another portion of flow line attached thereto positionable incoaxial register and spaced relationship with said first portion of saidcoupling means and connectable thereto, and prime mover means operablewith one portion of said coupling to connect the portions of saidcoupling together.

7. An offshore wellhead apparatus adapted to be positioned beneath thesurface of water, said apparatus including at least one string of wellcasing, and at least one string of Well tubing therein extending into awell drilled in the earth underlying said Water, a Wellhead assemblyclosing the top of said casing and removably secured thereto, saidWellhead assembly having flow passage means therethrough incommunication with the string of Well tubing, a production flow lineconnected to said Wellhead assembly for conveying production fluidtherefrom, remotely-actuatable coupling means connected in saidproduction flow line near said Wellhead assembly, a first portion ofsaid fiow line and a first portion of said couplin means being fixedlypositioned relative to said Wellhead assembly and lower-able therewithinto place on the top of said well casing, and a cooperating secondportion of said coupling means and another portion of flow line attachedthereto positionable in coaxial register and spaced relationship withsaid first portion of said coupling means, and remotely-controlledpower-actuated prime mover means carried by one portion of said couplingmeans for engaging an element of one portion with the other portion ofsaid coupling means in a fluidtight connection.

8. An offshore wellhead apparatus adapted to be positioned beneath thesurface of Water, said apparatus including at least one string of Wellcasing and at least one string of Well tubing therein extending into awell drilled in the earth underlying said water, a wellhead assemblyclosing the top of said casing and secured thereto, said Wellheadassembly having flow passage means therethrough in communication withthe string of well tubing, a production flow line connected to saidwellhead assembly for conveying production fluid therefrom,remotelyactuatable coupling means connected in said production flow linenear said wellhead assembly, a first portion of said flow line and afirst portion of said coupling means being fixedly positioned relativeto said Wellhead assembly and lowerable therewith into place on the topof aid well casing, means adapted to extend between said wellheadapparatus and the surface of said water for lowering and positioning acooperating second portion of said coupling means and another portion offlow line attached thereto in coaxial register and spaced relationshipwith said first portion of said coupling means, and remotely-controlledpower-actuated prime mover means carried by one portion of said couplingmeans for connecting together an element of one portion with the otherportion of said coupling means.

References (Zited in the file of this patent UNITED STATES PATENTS2,532,341 Shannon Dec. 5, 1950 2,808,229 Bauer et al. Oct. 1, 19572,841,961 Lucas July 8, 1958 2,854,215 Cox et a1 Sept. 30, 19582,923,531 Bauer et al. Feb. 2, 1960

